3. Authenticated copies of written laws and other publicdocuments must be produced when they can be procured but should they be refused by the competent authorities, then inferior proof may be admissible. Id.

4. When our own government has promulgated a foreign law or ordinance of a public nature as authentic, that is held sufficient evidence of its existence. 1 Cranch, 38 1 Dall. 462; 6 Binn. 321 12 Serg. & Rawle, 203.

5. When foreign laws cannot be proved by some mode which the law respects as being of equal authority to an oath, they must be verified by the sanction of an oath.

6. The usual modes of authenticating them are by an exemplification under the great seal of a state; or by a copy proved by oath to be a true copy - or by a certificate of an officer authorized by law, which must, itself, be duly authenticated. 2 Cranch, 238; 2 Wend. 411; 6 Wend. 475; 5 Serg. &. Rawle, 523; 15 Serg. & Rawle, 84: 2 Wash. C. C. R. 175.

7. Foreign unwritten laws, customs and usages, may be proved, and are ordinarily proved by parol evidence; and when such evidence is objected to on the ground that the law in question is a written law, the party objecting must show that fact. 15 Serg. & R. 87; 2 L. R. 154. Proof of such unwritten law is usually made by the testimony of witnesses learned in the law, and competent to state it correctly under oath. 2 Cranch, 237; 1 Pet. C. C. R. 225; 2 Wash. C. C. R. 175; 15 Serg. & R. 84; 4 John. Ch. R. 520; Cowp. 174; 2 Hagg. R. App. 15 to 144.

8. In England certificates of persons in high authority have been allowed as evidence in such cases. 3 Hagg. Eccl. R. 767, 769.

9. The public seal of a foreign sovereign or state affixed to a writing purporting to be a written edict, or law, or judgment, is, of itself, the highest evidence, and no further proof is required of such public seal. 2 Cranch, 238; 2 Conn. R. 85; 1 Wash. C. C. R. 363; 4 Dall. 413, 416; 6 Wend. 475; 9 Mod. 66.

10. But the seal of a foreign court is not, in general, evidence, without further proof, and it must therefore be established by competent testimony. 3 John. R. 310; 2 Harr. & John. 193; 4 Cowen, 526, n.; 3 East, 221.

11. As courts of admiralty are courts under the laws of nations, their seals will be admitted as evidence without further proofs. 5 Cranch, 335; 3 Conn. 171. This is an exception to the general rule.

12. The mode of authenticating the laws and records of the severalstates of the American Union, is peculiar, and will be found under the article Authentication. It may hereby be observed that the rules prescribed by acts of congress do not exclude every other mode of authentication, and that the courts may admit, proof of the acts of the legislatures of the several, states, although not authenticated under the acts of congress. Accordingly a printed volume, purporting on its face to contain the laws of a sister, state, is admissible, as prima facie evidence; to prove the statute law of that state. 4 Cranch, 384; 12 S. & R. 203; 6 Binn, 321; 5 Leigh, 571.

13. - 2. The effect of such foreign laws, when proved, is properly referable to the court; the object of the proof of foreign laws, is to enable the ourt to instruct the jury what is, in point of law, the result from foreign laws, to be applied to the matters in controversy before them. The court are therefore to decide what is the proper evidence of the laws of a foreign country; and when evidence is given of those laws, the court are to judge of their applicability to the matter in issue. Story, Cont. of L. §638 2 Harr. & John. 193. 219; 4 Conn. R. 517; 3 Harr. & John. 234, 242; Cowp. 174. Vide Opinion.